package com.mall.huohuo.openapi.config.auth;


import com.mall.huohuo.common.jwt.JwtUtils;
import com.mall.huohuo.common.constant.UserConstants;
import com.mall.huohuo.trace.TraceUtils;
import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.RequestMethod;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * jwtFilter 校验token
 */
public class JwtFilter extends BasicHttpAuthenticationFilter {

    /**
     * 判断用户是否想要登入。 检测header里面是否包含Authorization字段即可
     */
    @Override
    protected boolean isLoginAttempt(ServletRequest request, ServletResponse response) {
        HttpServletRequest req = (HttpServletRequest) request;
        String authorization = req.getHeader(UserConstants.USER_AUTHORITIES_KEY);
        return authorization != null;
    }

    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
        httpServletResponse.setHeader("reqeust-id", TraceUtils.getTrace());
        if (isLoginAttempt(request, response)) {
            boolean isLoginSuccess = executeLogin(request, response);
            if (isLoginSuccess) {
                return true;
            }
        }
        response401(response);
        return false;
    }

    @Override
    protected boolean executeLogin(ServletRequest request, ServletResponse response) {
        HttpServletRequest req = (HttpServletRequest) request;
        String token = req.getHeader(UserConstants.USER_AUTHORITIES_KEY);

        if (!JwtUtils.validateToken(token)) {
            return false;
        }

        try {
            getSubject(request, response).login(new JwtToken(token));
        } catch (Exception e) {
            return false;
        }

        return true;
    }

    private void response401(ServletResponse response) {
        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
        try {
            httpServletResponse.sendError(401);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * 对跨域提供支持
     */
    @Override
    protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
        httpServletResponse.setHeader("Access-control-Allow-Origin", httpServletRequest.getHeader("Origin"));
        httpServletResponse.setHeader("Access-Control-Allow-Methods", "GET,POST,OPTIONS,PUT,DELETE");
        httpServletResponse.setHeader("Access-Control-Allow-Headers", httpServletRequest.getHeader("Access-Control-Request-Headers"));
        // 跨域时会首先发送一个option请求，这里我们给option请求直接返回正常状态
        if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name())) {
            httpServletResponse.setStatus(HttpStatus.OK.value());
            return false;
        }
        return super.preHandle(request, response);
    }
}
